Torque direction for any system of particles

AI Thread Summary
The discussion centers on calculating the torque acting on a particle moving clockwise around the origin in the xy plane. The torque is determined using the equation τ = dL/dt, where L represents angular momentum. Participants express confusion about determining the direction of torque, particularly in relation to the right-hand rule. It is clarified that for clockwise motion, the torque direction is indeed negative along the z-axis, represented as -k. The conversation emphasizes the importance of correctly applying the right-hand rule to find torque direction in rotational motion scenarios.
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Homework Statement



A particle is to move in an xy plane, clockwise around the origin as seen from the positive side of the z axis. In unit-vector notation, what torque acts on the particle at time t = 9.5 s if the magnitude of its angular momentum about the origin is (a) 8.0 kg·m2/s, (b) 8.0t^2 kg·m2/s3, (c) 8.0t^(1/2) kg·m2/s3/2, and (d) 8.0/t^2 kg·m2*s?

Homework Equations



τ=dL/dt

The Attempt at a Solution



All i have to do is take the time derivative of the given angular momentum and plug in t. I can get the magnitude of the torque with the equation but i do not know how to get the direction of torque. Please explain! Thanks
 
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Look up the right hand rule :)
 
Well, I'm not too sure how to apply right hand rule with dl/dt, perhaps you can give me some insight?
 
Wait, do i just move my fingers to the direction its turning, in this case clockwise? If so then its -k, right?
 

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